Steel retainer



Nam Q 9 1926.

- mmwm C. C. HANSEN STEEL RETAINER Filed April 11.1925 3 Sheets-Sheet 1 INVENTOR l lzmzie$l llflm$en HISATTORN C. C. HANSEN STEEL RETAINER Filed'April 11. 1925 3 Sheets-Sheet 2 #185 ATTORN Y mnwm New, 9 H926.

C. C. HANSEN STEEL RETAINER Filed April 11. 1925 5 Sheets-Sheet 5 Fatented Nov. 9, 1926.

UNITED STATES PATENT OFFICE.

CHARLES C. HANSEN, OF EASTON, PENNSYLVANIA, ASSIGNOR TO INGEBSOLL-RAND COMPANY, OF JERSEY CITY, NEW JERSEY, A CORPORATION NEW JERSEY.

STEEL RETAINER.

Application filed April 11, 1925. Serial No. 22,258.

This invention relates to rock drills, but more particularly to steel retainers adapted to be applied to the front end of a hammer type rock drill. 4

One object of the invention is to prevent removal of the steel from the front head while the steel is being withdrawn from the drilled hole.

Another object is to prevent ejection of the steel from the front head while the drill is in operation, and a further object is to produce a rugged steel retainer having comparatively few parts which is inexpensive to manufacture, efficient in operation and which may be readily assembled and disassembled. A still further object is to produce a steel retainer which is normally held in retaining position andwhich will automatically spring to retaining position when the drill is inserted in the machine.

Other objects will be in part obvious and in part pointed out hereinafter.

The invention consists of the combination of elements and arrangements of parts having the general mode of operation hereinafter described and pointed out more particularly in the appended claims and illustrated in the accompanying drawings, in which Figure 1 is a sectional view in elevation of a front end of a rock drill showing the pawl in retaining position,

Figure 2 is a view similar to Figure 1 showing the pawl in releasing position,

Figure 3 is a transverse sectional vlew taken through Figure 1 on the line 33 looking in the direction of the arrows,

Figure 4 is a vertical sectional view in elevation of the front end of a rock drill showing a modification of the invention in which one side of the bearing portion of the pawl is recessed to permit the passage of the drill steel collar, 0

Figure 5 is a side view partly in section and taken through Figure I on the line 55 looking in the direction of the arrows,

Figure 6 is a modification of the lnvention showing a pawl at opposite sides of the drill steel,

Figure 7 is another modification of the invention showing the pawl in retaining position Figure 8 is a side view of Figure 7 partly broken away position, and

Figure 9 is a transverse sectional view taken through Figure 7 on the line 9--9 looking in the direction of the arrows.

Referring to the drawings, the invention is shown applied to a rock drill in which a cylinder A and a front head B are centralized by a front cylinder washer C and are held in operative position by the usual side bolts (not shown). Disposed within the cylinder A is a hammer piston D to reciprocate therein and deliver blows of impact on the shank E of a drill steel F. In this in stance the forward extension G of the piston D is provided with flutes H which coshowing the pawl in releasing operate with corresponding flutes J in a chuck K for imparting rotary movement to said drill steel. In this instance the chuck K carries a reduced extension L having a polygonal bore 0 to receive the shank E of the drill steel, and a face P of said extension cooperates with a collar Q, on the drill steel for limiting movement of said steel in one direction.

In accordance with the present invention, a V-shaped recess -R, terminating at the forward apex end in a bore S and at its rearward wider end in an aperture T, is formed transversely through the enlarged front end portion of the front head B. Disposed within said recess R and bore S is a pawl U having a cylindrical bearing portion V which also serves as a pivot for said pawl. Movement of the pawl in one direction is limited by a face W and in the other direction by a face X of the recess R. A handle Y is formed inte rally with the pawl for manipulating sai pawl and the pawl is preferably held against end-wise movement by a pin Z.

Means are provided for holding the pawl normally in retaining position, and to this end a plunger 6 and a spring 0 are arranged in a recess (Z so that the plunger 6 bears against the end of the pawl U and constantly holds said pawl against the face X of the recess R. In this position, an end face e of the awl U extends into the path of the collar 5 and cooperates therewith to limit movementof the steel in a forward direction as indicated by the dot and dash lines in Figure 1. In this instance, the pawl U is stantially the same 0 the pawl U is provided with a concave rearranged to incline toward the drill steel when in retaining position and may be rocked against the face IV of the front head to permit withdrawal of the steel. The recess d is also inclined at an angle to the longitudinal axis of the steel and is so arranged that the spring 0 forces the plunger 6 toward the drill steel and exerts its greatest force against the pawl when the pawl is in retaining position. By this arrangement of parts the pawl U also serves to retain the plunger 6 within the recess (Z.

In the operation of the device, let it be assumed that the pawl U and plunger 6 are in position indicated in Figure 1, and that a drill steel is about to be inserted into the machine. The shank E of the steel may be entered in the bore U of the chuck K and the pawl U may be depressed by pressing the collar Q against the inner face of the pawl, and after the collar passes the free end of the pawl, the pawl will automatically be pressed to its retaining posi-' tion by the spring 0 and the plunger 6.

The above described invention has been found to be extremely efiicient in operation and may be manufactured cheaply so that worn or broken parts may be replaced at a small expense. The advantages of this construction reside in the fact that few parts are required, and all the operative parts are protected inside of the front head. It will also be observed that none of the parts extend beyond the front end of the front head and are therefore well protected against injury or breakage frequently caused by driving the machine against the material being operated upon.

In the modification illustrated in Figures 4 and 5, is shown a pawl U having subaracteristics as the pawl described in connection with Figure 1. In this instance, the bore S is positioned so that it cuts through the bore 7 of the front head thereby reducing the inclination of the pawl when in retaining position. The inner face of. the cylindrical portion V of cess g to permit the passage of the collar Q on the drill steel F when inserting or removing the drill steel. A notch h is formed in the cylindrical portion of the pawl and provides a seat for the plunger 6 which in this instance is arranged transversely to the longitudinal axis of the machine and in addition to holding the pawl in its retaining position also serves to prevent accidental removal of the pawl from the front head in case the pin Z becomes lost. A trunnion j forms an extension of the cylindrical portionlv; to increase the bearing area of the paw In Figure 6 is shown a modification of the invention in which pawls II are arranged on oppositesides of the. drill steel F and at its outer end to receive a plug 0 which forms a bearing for the spring.

Another modification is illustrated in Figures 7, 8 and 9. In which, the retaining position of the pawl U is preferably at right angles to the axis of the drill steel, A recess p is formed in the face of the pawl and partly encircles the drill steel F. In this instance the trunnion j extends beyond the wall of the front head to receive a washer g and the pin 1" for holding the pawl against removal from the front head. A notch a is formed on the trunnion 7' to provide a seat for the plunger 5 when the pawl is in retaining position. In this instance, the outer end of the recess d is also screw threaded to receive a plug t. A recess u is formed on the inner face of the plug t to form a seat for the spring 0 and for centralizing said spring. A slot 4) is formed in the outer end of the plug 23 and is adapted to receive a v screw driver for screwing the plug 25 into the recess.

In all the forms of the invention illustrated, the pawl or pawls bear against the seat provided in the front head and do not bear against the steel so that the steel is. free to rotate without wear against the pawl o pawls.

' I claim:

1. In a fluid actuated rock drill, the cornbination of a front head adapted to receive the collared shank of a drill steel and having an enlarged front end portion formed with a transverse V-shaped recess open at one end for the insertion of a pawl from the side of the front head, the forward apex portion of the transverse recess terminating in a bore, and the rearward wider end having a recess through which the free end of the pawl is adapted to project towards the drill steel to form a stop, a solid fiat oscillating pawl having substantial length and breadth located in said recess and formed with a cylindrical bearing portion lying in the said forward bore-of the recess, and a spring pressed plunger for constantly forcing said pawl towards the drill Steel shank.

2. In a fluid actuated rock drill, the combination of a front head adapted to receive the collared shank of a drill steel and having an enlarged front end portion formed with a transverse V-shaped recess open at one end for the insertion of a pawl from the side of the front head, the forward apex portion of "and the rearward wider end having a recess through whichthe free end of the pawl is adapted to project towards the drill steel to form a stop, a solid flat oscillating pawl having substantial lengthand breadth located in said recess and formed with a cylindrical bearing portion lyin in the said forward bore of the recess, an a spring pressed plunger for constantly forcing said pawl towards the drill steel shank, the inner and outer faces of the transverse recess *intge front head forming stops for limitin swinging movement of the pawl, and a ger piece connected to the pawl and extending outside the front head for retracting the pawl to release the drill steel.

In testimony whereof I have signed this specification, I

' CHARLES C. HANSEN. 

